MICROSCOPE IN MANUFACTURES 



and most expensive fabrics. In a great deal of 

 really good cloth we may recognise other hairs 

 besides those of the sheep and sometimes vegetable 

 fibres find their way into good cloth by accident. 

 A piece of suspected cloth should be cut off and 

 separated as far as possible into its different 

 fibres. In shoddy we shall find few long fibres and 

 they will all be much torn for the reason that the 

 rags from which the material is made are cut up 

 in the manufacture. If we find cotton fibres, we 

 may be certain that our specimen is shoddy, also 

 if we can find fibres of many different colours, 

 though the final dyeing may have disguised the fact 

 that the fibres have originally figured in fabrics 

 of various colours. 



Silk is one of the most important of all fibres 

 capable of being woven into fabric. It is hardly 

 necessary to remark that it is formed by the 

 fully fed silkworm just before it turns into a 

 chrysalis. A very large number of caterpillars spin 

 silk but the majority of this silk is useless for 

 commercial purposes. The silkworm gives off a 

 double thread of silk from glands in its mouth and, 

 at the same time, it gives off a sticky substance 

 called silk glue which sticks the two fibres to- 

 gether, so that, to the eye at least they appear as 

 one fibre. 



Most of us have kept silkworms, those who have 

 not may find it worth while to expend a few pence 

 in some of these insects for the sake of examining 

 the raw silk. A cocoon, as the work of the cater- 



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